The present invention relates to a cordless communications system and, more particularly, to a cordless communications system wherein transmission is made between crew stations and a base station via magnetic lines of induction.
Conventional communications systems which employ generally known radio frequency techniques are not particularly suitable for military use where a high degree of security is desired. For example, with conventional HF and VHF walkie-talkies interference with existing radio, radar, navigation and ECM equipment is likely to occur. In addition, as an electrical field loses strength as the square of the distance from the transmitter, it is possible for communications to be intercepted. Furthermore, walkie-talkie systems presently employed experience numerous "blind spots" which result from (1) the inability of the electrical field to penetrate conductive materials and/or (2) re-radiation from conductive materials creating destructive interference. Finally, conventional radio frequency components used in known walkie-talkies are generally expensive and prone to failure.
Naturally, it would be highly desirable to provide a communications system which is intrinsically difficult to jam, eliminates interference with existing electronic equipment and has a high degree of security. Additionally, the communications system should be relatively compact, inexpensive and, in the case of crew stations, comfortable for the user.
Accordingly, it is the principal object of the present invention to provide a cordless communications system wherein transmission is made and received via magnetic lines of induction so as to provide an inherent high degree of security and elminates virtually all blind spots.
It is a further object of the present invention to provide a cordless communications system which is virtually impossible to jam.
It is a particular object of the present invention to provide a cordless communications system which is compact, readily portable and comfortable for the user to wear.
It is a still further object of the present invention to provide a cordless communications system having a crewset loop antenna which allows for freedom of movement while maintaining good magnetic coupling with the base station.
Further objects and advantages will appear hereinbelow.